Safety guard for duplicating machines



June 19, 195] c. w. HUGHSON SAFETY GUARD FOR DUPLICATING MACHINES Filed Feb. 4, 1946 a M. 2% Q.

INVENTOR CALEB W. HUGHSON ATTORNEY Patented June 19, i951 um-TED STATES OFFICE SAFETY GUARD FOR pU -LIoA rrNG MACHINES Caleb W. Hughson, Milton, Mass. Application February 4, 19 456,;SeriztlNo.-6 5;426

4 Claims. (ole-1015118 {Granted under the act of March 3, 1883,, as

stripper rolls of the paper ejecting mechanism thereof.

A popular type of duplicating machine empl oys a plurality of rolls to strip the copysheets from the gelatin coated copying drum. One-of -these stripper rolls hasa knurled surfaceand is positively driven in rotation. This driven stripper roll drives a second stripper roll through frictional contact therewith. Another or pre-stripping roll, similarly provided with a knurled surface, is rotatably mounted at its opposite ends between a pair of swingable arms, thus forming a bail cooperable with the stripper roll proper.

This bail is normally urged to such position as to cause the pre-stripper roll to lie in the path of a shoulder on the copying drum. As the copying drum is driven in paper feeding direction, a shoulder thereon engages the pre-stripper roll bail and swings it into cooperative engagement with'the second mentioned stripper roll, whereupon, the pre-stripper roll is driven in rotation. When the pre-stripper roll is in engagement with the second stripper roll, it is located adjacent to the driven stripper roll. The area between the driven stripper roll and the pre-stripper roll constitutes a region of peril to the fingers of the operator. This hazard is emphasized and increased when a copying sheet has become fouled in the machine, through inadvertence, improper feeding, or for any other reason. Under these circumstances, the operator in attempting to remove the entangled sheet is required to reach down into the machine, so that the fingers are brought within the immediate vicinity of these driven stripper rolls. Heretofore, on machines of this type, a stop plate for retaining the finished copy papers in position on a receiving platform has been positioned above these rolls. This conventional stop plate is fixed in the machine with its lower edge in alignment with the stripper rolls and spaced a short distance thereabove.

This plate in nowise prevents nor tends to prevent the operators fingers from being caught between the stripper rolls, since it in no manner straddles or covers the area between the rolls Accordingly, it is an object of the presentinvention to provide a guard for preventing the chance of the operators fingers, from being caught between the stripper rolls and to have this guard serve also as .a' stop plate for a stack .of copypapers following the ejection of the latter .by the stripper rolls to' the receiving table.

A further object of the present invention is to amended April 30, 1928; 3-70 Gr. 757) '2 7 provide a guard of the characterset, forth which is simple in design and construction, inexpensively manufactured and readily mountable in the duplicating machine. a

With the above and other objects and features in view, the invention will now be described with reference to the accompanying drawings which illustrate a preferred embodimentof the invention and will be, pointed out in the claims.

In the drawings;

Fig. 1 is a perspective view of the improved combination paper stop plate and safety uard;

Fig. 2 is a partial sectional elevation of certain of the paper ejecting elements of a duplicating machine with the guard mounted thereon and showing the pre-strippfir rollinits normal or disengaged position; and

Fig. 3 is a View similar to Fig. 2 but with the pie-stripper roll shown in engagement with the stripper roll.

Referring to Fig. 2. there is shown a ,portion H] of the half-section, copying drum with gelatin coating l2. This .drum is driven in counterclockwise direction as viewed in Fig, 2 and advances the copy sheets I4, one .by one, around to the sheet ejecting mechanism. The arrangement is such that the leading edge, [6. of the sheet l4 lies in the path of a pre-stripper roll [.8 when a shoulder 20 on the drum [0 engages the undersurface of said roll. Thepaper ejecting mechanism comprises in addition to the pre-stripper roll [8 a series of spaced, rubber, stripper rolls22 freely rotatable upon av shaft 24 extending trans.- versely of and fixedbetween the side walls (not shown) of the machine frame. Centrally above the rolls 2 is a transversely extending stripper roll .26 having a knurled surface and adjusted to lie in frictional contact with the surface of the rolls 22. The roll 26 is, arranged to be driven positively in rotation by well-known driving means (not shown) provided on these machines. The ore-stripper roll LB, has a knurled surface and is rotatably mounted at its opposite ends between a pair of similar .arms such as 28, the

arms 28, in turn, being pivoted as at 36 in the machine. frame, thusforming a ,bail that is swingable from the position shown in Fig. .2, clockwise, to the position shown in Fig. 3. The bail structure just describedis normally urged to the position shown in Fig. 2 by conventional spring means (not shown) provided on these machines.

In this position the roll l8 .lies in the path of the shoulder 20 of the .drum in. .As the drum l0 rotates counterclockwise to. deliverthe sheet [4 to the paper ejecting mechaIfiSI- theshoulder 20,

in cooperation with other conventional operating mechanism of the machine, causes the roll l8 and arms 28 to be driven upwardly. During this movement roll 26 engages the leading edge l6 of the sheet l4, brings it into frictional engagement with the rubber rolls 22 and finally into engagement with the driven stripper roll 26 to feed the sheet out of the machine as shown in Fig. 3. The sheet l4 when fully ejected will lie atop the stack 4| of previously ejected sheets which are held in receiving tray 42. Ideally, the ejected sheets will lie well below the exposed surface of rolls 22 and 26.

However, if sheets in stack 4! are allowed to accumulate to a point near the top of tray 42, it often happens that an ejected sheet or sheets will slide or be blown back against rolls 22 and 26. Such sheets might be carried by rolls 22 and 26 to the top of roll 26 and thence back into the path of drum unless prevented from so doin by a suitable paper stop.

Referring to Fig. 3, it is seen that when the rolls l8 and 26 are adjacent to each other a definite hazard is presented to the fingers of the operator and the chance of inadvertent or accidental catching of the operators fingers or any dangling apparel between the rolls is clear and open. The present invention provides a guard to prevent the possibility of such an accident. The guard is best shown in Fig. 1 and comprises an elongated strip of metal or other suitable material 32 having a turned over lip 33 along its upper edge for reinforcing the strip and a lengthwise extending, curved, flange or skirt 34 formed integral with and depending from its lower edge. The opposite ends of the strip 32 are provided with angularly disposed ears 36 having openings 38 therein for receiving the screws such as 46.

In mounting the guard in the machine, the presently used conventional paper stop plate (not shown) is dismounted by removing the screws 46 and the guard just described and illustrated in Fig. 1 substituted therefor. By taking up upon the screws 46 the guard is positioned relative to the rolls [8 and 26, so that the skirt 34 completely overlies the area between the pre-stripper roll I8 and the stripper roll 26, thus the flange or skirt 34 serves to insure positively against the ioperators fingers or wearing apparel from becoming caught between these rolls. The lower edge of the skirt 34 terminates at a point above the upper surface of the roll [8 (Fig. 3) with sufficient clearance to permit the latter to travel its arcuate path from the position shown in Fig. 2 to the position shown in Fig. 3 without interference thereto by the skirt. The upper end of skirt 34, which is also the lower edge of strip 32, is positioned closely adjacent to the surface of roll 26 but out of contact therewith to prevent stray sheets from slipping between roll 26 and strip 32.

In practice, the application of this guard to the duplicating machine presently used has not only precluded the possibility of accidental injury to the operator but has, as well, through its elimination of mental strain or fear of injury,

contributed greatly to the efficiency of the operator.

The invention described herein may be manufactured and used by or for the Government of the United States of America for government purposes without the payment of any royalty thereon or therefor.

Having described the invention what is claimed as novel and desired to be protected by Letters Patent of the United States is:

1. In a duplicating machine including a copying drum, a receiving tray, a driven stripper roll, a second stripper roll in contact therewith and a pre-stripper roll movable from a normally inactive position overlying the copying drum in a position to intercept the edge of a paper sheet carried by said copying drum to a second position adjacent to said driven stripper roll, a combination paper stop and safety guard comprising an elongated strip corresponding in length to the length of said rolls, said strip being mounted intermediate said copying drum and said receiving tray in a substantially upright position with the lower edge of said strip in close proximity to said rolls and a flange on said strip arranged to overlie the area between said driven roll and said pre-stripper roll when said pre-stripper roll is in said second position, whereby said strip functions as a paper stop plate and said flange serves as a safety guard.

2. In a duplicating machine including a copying drum, a receiving tray, a driven stripper roll, a second stripper roll in contact therewith and a pre-stripper roll movable from a normally inactive position overlying the copying drum in a position to intercept the edge of a paper sheet carried by said copying drum to a second position adjacent to said driven stripper roll, a combination paper stop and safety guard comprising an elongated strip corresponding in length to the length of said rolls, said strip being mounted intermediate said copying drum and said receiving tray in a substantially upright position with the lower edge thereof in close proximity to said rolls and serving as a paper stop plate, and a flange on Said strip arranged to overlie the area between said driven stripper roll and said prestripper roll when said pre-stripper roll is in said second position, the lower edge of said flange terminating at a sufficient distance from the surface of said second stripper roll to permit free movement of the pre-stripper r011 toward and away from an engaged position with said second stripper roll, said strip and said flange providing a safety guard to prevent the accidental insertion of objects between said rolls.

3. In a duplicating machine including a copying drum, 2. receiving tray, a driven stripper roll,

position to intercept the edge of a paper sheet carried by said copying drum to a second position adjacent to said driven stripper roll, a combination paper stop and safety guard comprising an elongated strip positioned intermediate said copying drum and said receiving tray, a curved skirt depending from and extending along one edge of said strip, and adjustable means for mounting said strip adjacent to said driven stripper roll in such a manner that said skirt completely covers the area between said driven stripper roll and said pre-stripper roll when said pre-stripper roll is in said second position, whereby said strip serves as a paper stop plate and said skirt serves as a guard to prevent the accidental insertion of objects between said rolls.

4. In a duplicating machine including a copying drum, a receiving tray, a driven stripper roll, a second stripper roll disposed substantially vertically below said driven stripper roll and in contact therewith, and a pre-stripper roll movable from a normally inactive position overlying the copying drum in a position to intercept the edge of a paper sheet carried by said copying drum to a second position adjacent to said driven stripper roll, the upper surface of said pre-stripper roll lying below the upper surface of said driven stripper r011 when said pre-stripper roll is in said second position, a combination paper stop and safety guard comprising an elongated strip corresponding in length to the length of said rolls, said strip being mounted substantially vertically in a position intermediate said copying drum and said receiving tray with the lower edge thereof adjacent the upper surface of said driven stripper roll, and a flange depending arcuately downward from said lower edge of said strip, said flange being arranged to overlie the area between said driven stripper r011 and said pre-stripper per roll, said strip and said flange providing a safety guard to prevent the accidental insertion of objects between said rolls, said strip also serving as a paper stop plate.

CALEB W. HUGI-ISON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,168,640 Hyams Jan. 18, 1916 1,220,620 Freeman Mar. 27, 1917 1,562,010 Stuke Nov. 17, 1925 1,883,258 Wood Oct. 18, 1932 1,926,317 Storck Sept. 12, 1933 2,012,105 Marchev Aug. 20, 1935 2,147,410 Marchev Feb. 14, 1939 2,188,600 Kropp Jan. 30, 1940 

